Recombinant Human NPEPPS Protein, CF

• 6 months from date of receipt, -70 °C as supplied.
• 3 months, -70 °C under sterile conditions after opening.

• Assay Buffer: 25 mM HEPES, 1 mM DTT, pH 7.0
• Recombinant Human Puromycin‑sensitive aminopeptidase/NPEPPS (rhNPEPPS) (Catalog # 6410-ZN)
• Substrate: Leu-AMC (Bachem, Catalog # I-1240), 10 mM stock in DMSO
• F16 Black Maxisorp Plate (Nunc, Catalog # 475515)
• Fluorescent Plate Reader (Model: SpectraMax Gemini EM by Molecular Devices) or equivalent

1. Dilute rhNPEPPS to 0.2 ng/μL in Assay Buffer.
2. Dilute Substrate to 20 μM in Assay Buffer.
3. Load 50 μL of 0.2 ng/μL rhNPEPPS into the microplate and start the reaction by adding 50 μL of Substrate. Include a Substrate Blank containing 50 μL of Assay Buffer and 50 μL of Substrate.
4. Read at excitation and emission wavelengths of 380 nm and 460 nm, respectively, for 5 minutes in kinetic mode.
5. Calculate specific activity:

     *Adjusted for Substrate Blank
     **Derived using calibration standard 7-amino, 4-Methyl Coumarin (Sigma, Catalog # A-9891.

• rhNPEPPS: 0.010 µg
• Substrate: 10 µM